As wireless technology advances toward more versatile mobile platforms, consumer demands within the wireless industry continue to drive convergence in the end mobile device. For example, mobile wireless devices and related equipment are trending toward a single mobile wireless platform, or system concept, effectively enabling system users to operate any single device over a wide range of communication platforms such as voice, data transmission, texting, multimedia video downloads, and other processing functions. Requirements of such multi-functional devices across diverse platforms, especially where these devices may be coupled to multiple accessories, will place additional strain on maintaining antenna performance from the embedded antennas in the mobile device.
Accordingly, there is a present demand for new techniques adapted to maintain antenna system performance, and further adapting the antenna system to function in view of changes in the operational environment of a given wireless device. Current antenna technology is not robust enough to provide the flexibility in optimization and re-tuning required as a mobile wireless device is coupled to other accessories designed to enhance the input and output functions desired by users to make the user experience more efficient. There further remains a need for improving power management and optimizing battery resources within communications devices.
A common problem encountered in mobile wireless communication systems is the de-tuning effects incurred on the antenna due to the multiple use cases for the device, such as for example: device held in the user's hand, device against the user's head, or placement of the device on a surface such as a table or dashboard of an automobile, etc. As the antenna de-tunes, the impedance presented by the antenna to a power amplifier and receiver varies, which in turn reduces the power transfer through the front end (power amplifier, switch assembly, filters, and antenna). The result is reduced communication range as well as reduced data rate for the communication device. With a passive antenna and fixed impedance matching circuit, the front end can only be optimized for a single use case. The added requirement for the mobile wireless device to operate when connected to or in close proximity to additional accessories presents additional challenges in maintaining optimization of the antenna system.